The Seven Colours of The Sky

http://www.slideshare.net/jesicagrace/the-seven-colours-of-the-sky 

Rainbow is an optical and meteorological phenomenon that is caused by both reflection and refraction light in water’s droplet in the Earth's atmosphere, resulting in a spectrum of light appearing in the sky. It takes the form of a multicoloured arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the sun.

All rainbows are full circles, however, the average observer only sees approximately the upper half of the arc, the illuminated droplets above the horizon from the observer's line of sight.

In a "primary rainbow", the arc shows red on the outer part and violet on the inner side. This rainbow is caused by light being refracted (bent) when entering a droplet of water, then reflected inside on the back of the droplet and refracted again when leaving it.

Rainbow can be seen after the rain. The perfect time and place to look for a rainbow needing bright sunlight in back and rain clouds off in the distance in the direction of your shadow. If it is later than 4.30 in the afternoon or earlier than 8.30 in the morning at these condition there is a very good chance to see a rainbow in the sky. Other places, rainbows can be seen in fountains, in the ocean as the waves crash against the rock which create a mist in the air, waterfalls, sprinklers and mist from a garden hose.

 How this is happened?

The rainbow is not located at a specific distance, but comes from an optical illusion caused by any water droplets viewed from a certain angle relative to the sun ray's. Thus, a rainbow is not an object, and cannot be physically approached. Indeed, it is impossible for an observer to see a rainbow from water droplets at any angle other than the customary one of 42 degrees from the direction opposite the sun. Even if an observer sees another observer who seems "under" or "at the end of" a rainbow, the second observer will see a different rainbow—further off—at the same angle as seen by the first observer.

A rainbow spans a continuous spectrum of colours. Any distinct bands perceived are an artifact of human colour vision and no banding of any type is seen in a black-and-white photo of a rainbow, only a smooth gradation of intensity to a maximum, then fading towards the other side. For colours seen by the human eye, the most commonly cited and remembered sequence is Newton's sevenfold red, orange, yellow, green, blue, indigo and violet.

There are 7 colours in the Rainbow

 

 

Red-Orange-Yellow-Green-Blue-Indigo-Violet

Yet few people realize that every color of the rainbow has its own deep-rooted psychological meaning. Here’s how this could help ensure that an annual report conveys all the right messages.

Red is active, powerful, stimulating, impulsive and successful. It’s attention-grabbing, and perfect for highlighting a company’s achievements during the year.

Orange represents physical excitement, abundance and enjoyment. It makes text stand out, and will really bring strings of divisional reports to life.

Yellow is fun, optimistic, creative and expressive of the desire for change – the ideal color for outlining future plans.

Green, being the center of the spectrum, is calm, reassuring, balanced and unchanging. Use this to emphasize your environmental record, or to take the sting out of bad news.

Blue and indigo are trustworthy, efficient and accurate, and ideal for indicating that your finances are healthy. Blue is also dependable, as in “true blue”.

Violet and purple are colors of quality, with charming, mystical and dreamy overtones. If they can’t give gravitas to the chairman’s letter, nothing will.

Shape of Rainbow

As we know, the rainbow just appears half of circle form, but actually the rainbow is a circle form. Rainbow can be seen perfectly, if it is seen by standing in the high place like in the air plane or standing on top of mountain. It is real that rainbow is a circle form not like parabola form. On the ground is not perfect but only half of circle form.

Interestingly, the location of the rainbow totally depends on the position of the person who can see it, and on the position of the sun relative to that person. If the sun is shining towards the eyes, rainbow can be seen. The sun needs to be behind the people, so that can see a rainbow and the sun at the same time.